Digital Ultrasound Imaging Techniques Using Vector Sampling and Raster Line Reconstruction
by Steve M. Gehlbach and Robert E. Alvarez
Published by the Academic Press, 1981. Ultrasonic Imaging 3, pp83-107 (1981).
The use of digital techniques in acoustic imaging is receiving a great deal of attention due to the power and flexibility of digital signal processing as well as its steadily decreasing cost. In this paper we describe the theory and preliminary experimental results for a digital synthetic aperture imaging system which uses one or more transmit/receive cycles to gather data for reconstructing an entire image. The system uses quadrature frequency conversion prior to digitization to reduce the data rate and storage requirements. Using this approach, an imaging instrument design is presented that has the capability of reconstructing images in real time in TV format without conventional scan conversion. Freeze frame is also possible although no image memory is required.